Definitely Fist of the North Star for the Genesis, also known as "Last Battle".
> > I want to know the name and console of this game: It's a simple side scrolling
> > beat'em up where a guy have to beat some street 'ninja' punks and guys that
> > comes riding motorcycles and In certain points, he increases his power and he
> > rips off his shirt showing his worked muscles, like in Altered Beast (I think
> > it's a Genesis or Snes game - maybe Master System). If I remember correctly,
> > have to defeat some bosses from different locations in order to complete the
> > game.
> > Please help!!!!!!!!!!!